Protective device for dishwasher door



FIG!

INVENTOR.

JOHN A. DKKEN IP..

k-Ms ATTORNEY United states Pat-em; o

. 3,383,148 PROTECTIVE DEVICE FOR DISHWASHER DOGR John A. Dicken, Jr., Louisville, Ky., assigner to General Electric Company, a corporation of New York Filed Aug. 15, 1966, Ser. No. 572,567 6 Claims. (Cl. 312-311) ABSTRACT F THE DISCLOSURE This invention relates generally to automatic dishwashers and, more specifically, to a protective device to prevent damage to the plastic coating on the inner surface of a dishwasher door.

lMany manufacturers of automatic dishwashers employ cold-rolled steel for such structural members as the dishwasher tub, cabinet and door. Because this material will oXidize and deteriorate under the inuence of moisture and elevated temperatures as are present in dishwashers, various coatings have been employed to protect the material from moisture. One of the most suitable materials is polyvinyl chloride plastisol which not only provides moisture protection but further provides, due to its resiliency, a

cushioning effect which minimizes chipping and marringr of the dishes and other articles being washed. Polyvinyl chloride plastisol also provides some degree of sound insulation thus reducing the sound level of the machine during operation. However, polyvinyl chloride plastisol has the disadvantage ot -being susceptible to abrasion and laceration when subjected to contact with rough or shanp articles. For example, if the sharp edge of a steak knife or the sharp point of a fork tine is passed across the plastisol surface, the plastisol may be cut completely through to the cold-rolled steel. The cut then allows moisture to contact the steel, at the elevated temperature present in a dishwasher, which will eventually result in oxidation and deterioration of the metal beneath the plastisol coating. The integrity of plastisol must be maintained in order for it to perform suitably.

Although other causes may exist, the principal cause of abrasion or laceration is contact between knives and forks, disposed within the silverware basket, and the opened door when the dish-supporting rack is moved out of the wash -chamber onto the door or into the wash chamber from the door. In most drop-door dishwashers, i.e., dishwashers having a door pivotal -between a substantially vertical closed position and a substantially horizontal lopen position, the lower dish-supporting rack iS provided with rollers which allows it to be rolled at least partially out of the wash chamber onto the upwardly facing inner surface of the opened door.

It has been found in practice that if a flat protective device is directly applied to the vinyl plastisol coating, moisture will find its way under the device and the continued presence of moisture and contact with the protective device will create blistering of the plastisol coating. The blisters will eventually burst or crack thus allowing the moisture to contact the steel in a manner similar to that achieved with an abrasion or laceration. As a result, the application of a protective device, of sufficient 3,383,148 Patented May 14, 1968 'ice area to provide suitable protection against abrasion or laceration, directly to the plastisol coating usually creates the identical problem it is intended to solve.

Accordingly, it is an object of the present invention to provide a protective device for a dishwasher door to protect the door against abrasive or lacerative injury to the vinyl plastisol coating on the door.

It is another object of the present invention to provide a protective device for a dishwasher door to prevent injury to the coating on the door particularly from silverware carried by the silverware basket.

It is a further object of the present invention to provide a protective device, of the type described, which minimizes blistering of the plastisol coating beneath the protective device.

Other objects will become evident as this description proceeds.

`In accordance with one aspect of the present invention, there is provided a protective device for use in a dishwasher having a door pivotal between a substantially vertical closed position and a substantially horizontal open position. The dishwasher further includes a dish-supporting rack movable to a position over the door when the door is in its open position. A silverware basket is carried by the dish-supporting rack and the inner surface of the ydoor is coated with a vinyl plastisol. At least a portion of the inner surface is in close proximity to the silverware basket when the dish-supporting rack is in its position over the door. The protective device comprises a shield portion having generally the configuration of the portion of the door to be protected. Spacer means are provided and are adapted to contact the inner surface of the door and maintain the shield portion spaced from the inner surface of the door. The spacer means has an area of contact with the door substantially less than the are-a of the shield portion. Securing means are provided to secure the shield portion and the spacer means relative to the door.

While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter which is regarded as the invention, it is believed the invention will be better understood from the following description taken in connection with the accompanying drawing, in which:

FIGURE 1 is a perspective view of an automatic dishwasher employing the present invention;

FIGURE 2 is a fragmentary elevational View, partially cut away to show details, of the dishwasher of FIG- URE 1;

FIGURE 3 is an elevational view ofthe preferred form of the protective device of the present invention;

FIGURE 4 is an end view of the protective device of FIGURE 3; and,

FIGURE 5 is a sectional view taken along line 5-5 of FIGURE 3.

Referring now to the drawing and particularly to FIGURE 1 thereof, there is illustrated an automatic dishwasher 10 having an outer cabinet 11 and an inner cabinet 12. A wash chamber is defined within inner cabinet 12 and contains an upper dish-supporting rack 13 and a lower dish-supporting rack 14. A door 15 is provided to allow access to the wash chamber so that articles may be placed therein or removed therefrom. Racks 13 and 14 are adapted to be at least partially withdrawn from the wash chamber out through the access opening when door 15 is in the open position. It is to be understood that door 15 has a substantially horizontal open position, as illustrated in FIGURES 1 and 2, and a substantially vertical closed position wherein the access opening is sealed to avoid the escape of wash liuids from the wash chamber.

[Withdrawal of ra-cks 13 and 14 may be provided in any convenient fashion. For example, rack 13 may be provided with slide out mechanism (not specifically shown) as described and claimed by Norman L. Kendt in U.S. Patent 3,096,425, issued July 2, 1963, and assigned to the General Electric Company, assignee of the present invention. Since the exact mechanism provided is not critical to the present invention, it is not shown nor described in detail herein.

Lower rack 14 is provided with a plurality of rollers 16 which rest upon a track 17 formed in the sidewall of cabinet 12. It is understood that a track 17 is provided at each side of the wash chamber and rollers 16 are provided at each of the four corners of rack 14. Thus, the rack 14 is free to move relative to cabinet 11 into and out of the wash chamber with rollers 16 rolling along track 17. Door 15 is provided with a pair of tracks 18,one adjacent each edge of the door, which align themselves with the tracks 17 when door 15 is in its open position. Thus, rack 14 may be movable to a position over the door, as illustrated in dotted line in FIGURE 2, when the door is in its open position. The rollers 16 at the front of rack 14, i.e., near door 15 are spaced from each other a distance sufficient so that the roller farthest from door 15 will ride along the track 17 while the other roller passes over the gap between tracks 17 and 18. Similarly, one roller will ride along track 18 during the time which the other roller is passing over the gap.

As is the case with most domestic automatic dishwashers available today, a special receptacle such as silverware basket 19 is provided to receive and contain silverware within the wash chamber. Silverware basket 19 may be formed integrally with rack 14 or may be a separate element supported by rack 14. In the embodiment described herein, sliverware basket 19 is a separate element and is provided with a pair of handles 20 which facilitate the removal of silverware basket 19 from rack 14 so that it may be transported to the kitchen table so that all the silverware may be loaded at the table. Housewives are normally instructed to insert the silverware into silverware basket 19 in the manner illustrated in FIG- URES 1 and 2. It should be understood, however, that during the normal operation of dishwasher 10 a significantly larger number of pieces of silverware will be contained within silverware basket 19 than the number illustrated.

As discussed above, he door 15 and cabinets 11 and 12 are conventionally formed of cold-rolled steel. Outer cabinet 11 is usually painted to provide a protective, as well as a decorative, coating. The inner surfaces of the dishwasher, such as inner cabinet 12 and inner surface 21 of door 15, are provided with a coating which will, under normal conditions of use, protect the underlying steel from deleterious affects of relatively high temperature and moisture. When the protective coating on cabinet 12 and inner surface 21 is a resilient plastic coating such as polyvinyl chloride plastisol, the abrasion and laceration problems discussed above may be encountered. These problems may be better understood by reference to FIGURE 2 wherein a relatively sharp knife 22 is shown supported by silverware basket 19. As will be obvious to those skilled in the art, sliverware basket 19 must have an open grid bottom to allow the wash fluid to enter silverware basket 19 to effectuate a wash action on the silverware supported therein. Of course, it is also necessary to provide an open grid work bottom for silverware basket 19 to allow the wash fluid to drain from the silverware basket so that the articles therein may be suitably dried during the terminal portion of the operational cycle of dishwasher 10. The size of the openings in the grid work bottom of silverware basket 19 are generally maintained as small as possible consistent with the admission of sufficient wash tiuid to clean the articles therein. However, pointed steak knives or carving forks, which have generally two slender widely spaced tines, may pass partially through the openings in the bottom of the silver- 4 ware basket. They may very likely project therebelow sufficiently to engage and lacerate the inner surface 21 of door 15 as silverware basket 19 passes thereover during removal from, or insertion into, the wash chamber.

Frequently, a dishwasher door will have a projection such as projection 23 near the bottom edge of the door. This projection is designed to cooperate with the marginal portion of the cabinet 12 along the bottom of the access opening to provide -a seal so that water cannot escape during operation of the dishwasher when door 15 is closed. It is this projection 23 which is most susceptible to laceration and abrasion.

In accordance with the present invention, a protective device 24 is provided to prevent damage to the coating on the inner surface 2.1 of door 15. Protective device 24 includes a shield portion 25 which has generally the same configuration of the portion of the door over which its is designed to lie. In the case of the structure shown in FIGURES 1 and 2, shield portion 25 has generally the configuration of projection 23. Securing means, in the form of lugs 26, are provided to project through openings in surface 21 of door 15. Lugs 26 are adapted to receive self-threading nuts 27 on the opposite side of surface 21 so that protective device 24 may be secured to surface 21. In the preferred form of the present invention, protective device 24 is formed of a molded plastic compound capable of withstanding the abrasive and lacerative effects of knives and forks as described above, and lugs 26 are molded integrally with shield portion 25 so that protective device 24 is an integral element.

As mentioned above, if shield portion 25 were applied directly to the plastisol coating on surface 21, moisture would inevitably find its way under shield portion 25 and the continued presence of moisture and contact with the protective device would create blistering of the plastisol coating. In order to avoid this phenomenon, spacer means 2S are provided to maintain shield portion 25 in spaced relationship with inner surface 21. Spacer means 28, in the preferred form of the present invention, comprise relatively narrow elongated protrusions extending substantially the full dimension of the shield portion in the direction of their elongation. Also, inasmuch as the preferred form of the present invention finds protective device 24 formed from a molded plastic, spacer means 28 would be integrally molded with shield portion 25 and lugs 26.

It is to be noted that spacer means 28 are in direct contact with the plastisol coating on inner surface 21. However, the area of Contact between spacer means 28 and inner surface 21 is substantially less than the area of shield portion 25. The area of shield portion 25 is determined primarily by the size of silverware basket 19 and the area of inner surface 21 to be protected. In any event, the area of shield portion 25 is in the magnitude of 20 to 100 square inches. The assignee of the present invention employs a protective device, identical to that illustrated in the drawings, having a shield portion with an area of approximately 40 square inches. By contrast, the area of spacer means 28 in direct contact with inner surface 21 is less than 2 square inches in the device employed by the assignee of the present invention. Thus, the area of contact between spacer means and the inner surface of the door is substantially less than the area of the shield portion. It has been found in practice that with such minimal larea of contact between the spacer means and the inner surface of the door, blistering will not occur. This is particularly true when the area of contact is of an elongated nature such as that provided by the elongated spacer means 28 illustrated in FIG- URE 3.

Since the environment within an automatic dishwasher inherently involves food particles which have been removed from the soiled dishes, it is conceivable, and in fact likely, that such food particles will find their way into the space between shield portion 25 and inner surface 21. If wash fluid is prevented from thoroughly flushing out the space between shield portion 25 and inner surface 21, these food particles may collect and in time will create obvious problems. Accordingly, the present invention contemplates providing a plurality of openings 29 which will allow wash fluid to enter the space between shield portion 25 and inner surface 2l to flush any collected food particles therefrom. Also, openings 29 allow free flow of air through the space to facilitate drying of the surfaces defining the space during the terminal portion of the operational cycle of dishwasher 1t); This drying effect further minimizes the possibility of blistering occurring at the points of Contact between spacer means 28 and inner surface 21.

If desired, stifening ribs 30 may be provided adjacent the ends of shield portion 25 to enhance the rigidity of protective device 24. It will be noted that ribs 36 are of shorter projection than spacer means 2S so that they do not contact inner surface 21.

Thus it can be seen that the present invention provides a protective device for a dishwasher door to protect the door against abrasive or lacerative injury to the vinyl plastisol coating on the inner surface of the door. Particularly, the present invention provides a device to protect against damage by silverware carried in the silverware basket. Moreover, the present invention minimizes blistering of the plastisol coating beneath the protective device.

As will be evident from the foregoing description, certain aspects of the invention are not limited to the particular details of construction of the example illustrated, and it is contemplated that various other modifications or applications will occur to those skilled in the art. it is therefore intended that the appended claims shall cover such modifications and applications as do not depart from the true spirit and scope of the invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

l. In a dishwasher having a door pivotal between ya substantially vertical closed position and a substantially horizontal open position, a dish-supporting rack movable to a position over said door when said door is in said open position, and a silverware basket carried by said dish-supporting rack, the inner surface of said door being coated with a plastic material susceptible to abrasion and laceration and having at least a portion thereof in close proximity to said silverware basket when said dishsupporting rack is in said position over said door, a protective device comprising:

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(a) a shield portion having generally the configuration of said portion of said door,

(b) spacer means ladapted to contact the inner surface of said door and maintain said shield portion spaced therefrom,

(c) said spacer means having an area of contact with said door substantially less than the area of said shield portion, and

(d) securing means to secure said shield portion and said spacer means relative to said door.

2. The invention of claim l wherein said shield portion has an upper edge and a lower edge when said door is in said closed position and said shield portion has a plurality of openings adjacent said upper edge to allow wash fiuid to pass therethrough to flush out the space between said shield portion and the inner surface of said door.

3. The invention of claim `1 wherein said protective device is molded of plastic and said spacer means are integrally formed with said shield portion.

4. The invention of claim 1 wherein said spacer means comprises a plurality of relatively narrow elongated protrusions extending substantially the full dimension of said shietd portion iu the direction of their elongation.

S. The invention of claim 1 wherein said protective device is molded of plastic and said securing means cornprise integrally formed protrusions adapted to project through openings in said door and further adapted to each receive a self-threading nut.

6. The invention of claim 1 wherein said shield portion has a plurality of openings adjacent one edge to allow ywash iuid to pass therethrough to flush out the space between said shield portion and the inner surface of said door.

References Cited UNITED STATES PATENTS 2,657,697 ll/l953 Walker 312-311 XR 2,937,063 5/1960 Kahn 312-229 3,972,452 1/1963 Sleeper 312-311 XR 3,098,685 7/1963 Stiner 312-311 3,295,541 1/1967 Ummel 134-182 3,338,542 8/1967 Meinhard 24S-345.1

ROY D. FRAZER, Primary Examiner.

A. FRANKEL, Assistant Examiner. 

